Ejemplo n.º 1
0
    def train_step(batch):
        with tf.GradientTape() as tape:
            output_batch = it_network(batch, training=True)
            output_batch = 255 * (output_batch + 1.0) / 2.0  # float deprocess

            # Feed target and output batch through loss_network
            target_batch_feature_maps = loss_network(batch)
            output_batch_feature_maps = loss_network(output_batch)

            c_loss = content_loss(
                target_batch_feature_maps[hparams['content_layer_index']],
                output_batch_feature_maps[hparams['content_layer_index']])
            c_loss *= hparams['content_weight']

            # Get output gram_matrix
            output_gram_matrices = [
                gram_matrix(x) for x in output_batch_feature_maps
            ]
            s_loss = style_loss(target_gram_matrices, output_gram_matrices)
            s_loss *= hparams['style_weight'] / num_style_layers

            total_loss = c_loss + s_loss
            scaled_loss = optimizer.get_scaled_loss(total_loss)

        scaled_gradients = tape.gradient(scaled_loss,
                                         it_network.trainable_variables)
        gradients = optimizer.get_unscaled_gradients(scaled_gradients)
        #gradients = tape.gradient(total_loss, it_network.trainable_variables)
        optimizer.apply_gradients(
            zip(gradients, it_network.trainable_variables))

        total_loss_avg(total_loss)
        content_loss_avg(c_loss)
        style_loss_avg(s_loss)
Ejemplo n.º 2
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    def train_step(content_img, style_img):
        t = transformer.encode(content_img, style_img, alpha=1.0)

        with tf.GradientTape() as tape:
            stylized_img = transformer.decode(t)

            _, style_feat_style = vgg(style_img)
            content_feat_stylized, style_feat_stylized = vgg(stylized_img)

            tot_style_loss = args.style_weight * style_loss(
                style_feat_style, style_feat_stylized)
            tot_content_loss = args.content_weight * content_loss(
                t, content_feat_stylized)
            loss = tot_style_loss + tot_content_loss

        gradients = tape.gradient(loss, transformer.trainable_variables)
        optimizer.apply_gradients(
            zip(gradients, transformer.trainable_variables))

        train_loss(loss)
        train_style_loss(tot_style_loss)
        train_content_loss(tot_content_loss)
Ejemplo n.º 3
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    def train_step(images):
        with tf.GradientTape() as tape:

            transformed_images = transformer(images)

            _, content_features = extractor(images)
            style_features_transformed, content_features_transformed = extractor(
                transformed_images)

            tot_style_loss = args.style_weight * style_loss(
                gram_style, style_features_transformed)
            tot_content_loss = args.content_weight * content_loss(
                content_features, content_features_transformed)

            loss = tot_style_loss + tot_content_loss

        gradients = tape.gradient(loss, transformer.trainable_variables)
        optimizer.apply_gradients(
            zip(gradients, transformer.trainable_variables))

        train_loss(loss)
        train_style_loss(tot_style_loss)
        train_content_loss(tot_content_loss)
Ejemplo n.º 4
0
layer_features = outputs_dict['block5_conv2']
content_image_features = layer_features[0, :, :, :]
generated_features = layer_features[2, :, :, :]
loss += content_weight * utils.content_loss(content_image_features,
                                            generated_features)

feature_layers = [
    'block1_conv1', 'block2_conv1', 'block3_conv1', 'block4_conv1',
    'block5_conv1'
]

for layer_name in feature_layers:
    layer_features = outputs_dict[layer_name]
    style_features = layer_features[1, :, :, :]
    generated_features = layer_features[2, :, :, :]
    sl = utils.style_loss(style_features, generated_features, num_rows,
                          num_cols)
    loss += (style_weight / len(feature_layers)) * sl
loss += total_weight * utils.total_loss(generated_image, num_rows, num_cols)

# Gradients of the generated image wrt the loss
grads = K.gradients(loss, generated_image)

outputs = [loss]
if isinstance(grads, (list, tuple)):
    outputs += grads
else:
    outputs.append(grads)
f_outputs = K.function([generated_image], outputs)

x = proc.preprocess_image(content_image_path, num_rows, num_cols)
Ejemplo n.º 5
0
        matrix[0, 2] = -np.sin(angle)
        matrix[1, 1] = np.sin(angle)
        matrix[2, 1] = np.cos(angle)
        matrix[2, 2] = 1.
        # print(matrix)
        return matrix

    def pad_matrix(matrix):
        return np.hstack([matrix, np.zeros((3, 1))])

    samples_x = samples[:, 0]
    samples_y = samples[:, 1]
    samples_z = samples[:, 2]
    for i in range(batch_size):
        theta[i] = pad_matrix(
            np.dot(np.dot(rot_z(samples_z[i]), rot_y(samples_y[i])),
                   rot_x(samples_x[i])))
    theta = torch.from_numpy(theta).float()
    z = torch.randn(batch_size, 128)
    G = Generator()
    img = G(z, theta)
    print(img.size())

    D = Discriminator()
    rf, z, logits = D(img)
    print(rf.size(), z.size(), logits[0].size(), logits[1].size(),
          logits[2].size(), logits[3].size())

    from utils import style_loss
    print(style_loss(logits, logits))